docs: def convert_multiPlanesRupture(self, node):
          """
          Convert a multiPlanesRupture node.
  
          :param node: the rupture node
          """
          mag, rake, hypocenter = self.get_mag_rake_hypo(node)
          with context(self.fname, node):
              surfaces = list(node.getnodes('planarSurface'))
          rupt = source.rupture.BaseRupture(
              mag=mag, rake=rake,
              tectonic_region_type=None,
              hypocenter=hypocenter,
              surface=self.convert_surfaces(surfaces))
          return rupt